The invention relates to a phased-array antenna of the type comprising a plurality of transmit/receive radiator elements arranged linearly, i.e., in rows, and in columns, a power distribution and phase shifter network for generating predetermined transmit/receive characteristics of the signals that are emitted and/or received by the transmit/receive radiator elements, and wherein a transmit/receive change-over takes place for the selective connection of the power distribution and phase shifter network to a transmitting and/or receiving arrangement.
Such antennas, particularly for radar applications, were disclosed, for example, in the German Unexamined Published Patent Applications DE-A 38 03 779, published Aug. 17, 1989, and DE-A 39 02 739, published Aug. 9, 1990, the subject matter of both of which is incorporated herein by reference. The arrangements or arrays described therein are substantially comprised of a plurality of transmit/receive radiator elements which are arranged linearly, e.g., in rows, or in the shape of a matrix. These transmit/receive radiator elements are connected to a transmitting/receiving arrangement known per se via a phase shifter arrangement, a power distribution network and a transmit/receive switch, e.g., in the form of a circulator. The power distribution network and the phase shifter arrangement serve to electronically form and/or swing a transmitting/receiving lobe. A decoupling of the transmit/receive signals is accomplished by the transmit/receive switch.
An arrangement of this type has the drawback that it is technically complex because a plurality of complex components is needed.
It is therefore the object of the invention to improve an arrangement of the generic type described above such that technically complex components, particularly the circulator, can be omitted.